Rotary flexible propeller



March 31, 1931. u. ANTON! 1,798,299

' ROTARY FLEXIBLE PROPELLER J Filed D90.- 30, 1927 a. in/am' Patented Mar. 31, 1931 i Q UNITED AsTATs PATENT OFFICE UGO ANTONI, 02B VIABEGGIO, 'I'LPALY 1210mm FLEXIBLE PBOPELLER Application filed December 30, 1927, Serial No. 243,732, and in Italy December 31, 1928.

It is well known that according'to practice and experience, rotary flexible propellers cannot reach a degree of perfection required for their use if the plane of the wings per- 5 pendicular to the driving axle cannot be deformed.

In preceding inventions of applicant the method was tried to have a gradual diminution of the wings thickness but it was not possible to obtain a distribution of the clasticity inversely proportional to the resistance met by the wings on the axis of rotation.

To prevent said inconvenience and obtain a greater efficiency applicant has found that wings should be constructed with a fore edge whose resistance decreases in the direction of arrow A, and also in the plane in direction v of arrow B to provide the flexible surface C, thus producing a larger and more flexible surface (Fig. 1)- which even when rotating with a smaller radius than the peripherical zone as regards the axis R possesses a greater flexibility with more parts normal to axis H (Fig. 2) which may be deflected, the eificiency consequently becoming very high.

Fig. 3 shows a wing without the surface C inscribed in Fig. 1, and consequently of a very scarce efiiciency during flexures.

Having now particularly described and ascertained the nature of my said invention andin what manner the. same is to be performed I declare that what I claim is:

A flexible rotating propeller blade having its fore edge proportioned in thickness to the resistance made in movement, the rear edge of the blade terminating in a prolonged section having greater flexibility than the blade, said section having its medial line in the central zone of the blade.

In testimony whereof I have hereunto signed my name.

. UGO ANTONI. 

